Methane, an abundant energy resource, is the main component of natural gas, which is largely produced from shale-gas formations. Conversion of methane to oxygenates, e.g., methanol and acetic acid, is of great importance. Indeed, it has attracted much attention, given broad applications of oxygenates in the chemical field.
Most current processes indirectly convert methane to methanol or acetic acid, which require multiple steps. For example, methane is converted to methanol through a two-step process (i.e., steam reforming methane to syngas and then transforming the syngas to methanol) and methane is converted to acetic acid via a three-step process (i.e., steam reforming methane to syngas, transforming the syngas to methanol, and finally converting the methanol to acetic acid).
Direct conversion of methane to methanol or acetic acid is becoming more popular than the current processes. Yet, there are three major disadvantages associated with current direct conversion of methane to methanol or acetic acid: use of an expensive oxidant, e.g., H2O2, low yield, and poor selectivity.
There is a need for a new method that directly converts methane to methanol or acetic acid, employs an inexpensive oxidant, and affords high yields and selectivity.